1. Field of the Invention
The present invention relates to an image forming apparatus where a cover is pivotably attached to a body frame and where a conveyance unit that conveys a recording medium and an intermediate transfer belt to which an image is transferred from a photosensitive body (image carrier) are attached to the cover.
2. Description of the Related Art
Conventionally, image forming apparatus have been known where a toner image formed on a photosensitive body (image carrier) or an intermediate transfer belt (belt member) is transferred/fixed to recording paper (a recording medium) to form an image. Among such image forming apparatus, there are image forming apparatus where a cover is pivotably attached to a body frame disposed with the photosensitive body or the intermediate transfer belt, and where the photosensitive body or the intermediate transfer belt is exposed by opening the cover (e.g., see Japanese Patent Application Publication (JP-A) No. 2001-201982).
Sometimes, a conveyance unit including a conveyor belt that conveys the recording paper is attached to the cover. In such cases, there is the advantage that even if a paper jam occurs while the recording paper is being conveyed, the recording paper causing the paper jam can be easily removed by opening the cover.
However, there is also the problem that when the image forming apparatus is configured in this manner, the conveyance unit (conveyor belt) becomes displaced in the main scanning direction (width direction of the conveyor belt) while the conveyor belt is traveling due to rattling of the cover with respect to the body frame (particularly rattling in the width direction of the conveyor belt). If such positional displacement occurs during printing in full color, the conveyance position of the recording paper shifts slightly per color; thus, there is the drawback that displacement occurs in the color registration. This drawback is also common to image forming apparatus where the intermediate transfer belt is attached to the cover.